共查询到20条相似文献,搜索用时 15 毫秒
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J Thulesen PE J?rgensen O Torffvit E Nex? SS Poulsen 《Canadian Metallurgical Quarterly》1997,72(2-3):179-186
This study was conducted to assess the predictive value of different variables including the response to dexamethasone suppression test (DST), in 105 patients with resistant depression after the addition of lithium (600 to 800 mg/day) for 4 weeks to antidepressant medication. Clinical remission was observed in 57 patients and no improvement in 48. A dramatic and rapid relief of depression occurred in 12 patients. Variables with significant or marginally significant differences between responders and non-responders were included in a stepwise logistic regression model. Weight loss (P = 0.0013) and depressive psychomotor activity (P = 0.045) in the Newcastle diagnostic index (NDI) scale, and overall score of the Hamilton Rating Scale for Depression (HRSD) before adding the lithium (P = 0.0039) were significantly associated with clinical remission. The difference in post-DST cortisol plasma levels between both groups was marginally significant. The logistic equation resulted in a sensitivity of 78% and a specificity of 65% and total correct classification of the lithium-added response of 72%. The clinical profile of patients who improve with the addition of lithium may include significant weight loss, psychomotor retardation and possibly, poor control of cortisol secretion. Partial remission before adding lithium as well as endogenomorphic traits according to NDI may also be considered additional criteria for response. 相似文献
3.
Hoxb-5 is one of the few homeobox genes strongly expressed in the developing mouse lung. To explore the hypothesis that Hoxb-5 acts to regulate epithelial cell fate and branching morphogenesis in the developing lung, we studied the temporal, spatial, and cell-specific expression of Hoxb-5 from gestational day (d) 13.5 to postnatal day (P) 2. Immunocytochemistry demonstrated regional localization of Hoxb-5 protein to developing conducting airways and surrounding mesenchyme. The cellular expression pattern changed from diffusely positive nuclei of mesenchymal cells on d13.5 to become more localized to nuclei of subepithelial fibroblasts and some adjacent columnar and cuboidal epithelial cells on d14.5. After d14.5, Hoxb-5 protein expression continued to decrease in mesenchymal cells distal from developing airways, but persisted in fibroblasts underlying conducting airways. Hoxb-5 protein expression persisted in nuclei of columnar and cuboidal epithelial cells on d16.5 and d17.5, with expression in low cuboidal epithelial cells as well from d17.5 to P2. Western blot analysis showed temporal and quantitative changes in Hoxb-5 protein expression with peak expression on d14.5-15.5. We conclude that Hoxb-5 protein is developmentally regulated in a temporal, spatial, and cell-specific manner throughout the pseudoglandular, canalicular, and terminal saccular periods of lung development in the mouse. This localization and expression pattern suggests that Hoxb-5 may influence branching morphogenesis, cell-cell communication, cell fate, and differentiation of conducting airway epithelia. 相似文献
4.
We investigated a possible causal relation between exposure to organic solvents in Danish workers (housepainters, typographers/printers, carpenters/cabinetmakers) and onset of multiple sclerosis. Data on men included in the Danish Multiple Sclerosis Register (3,241 men) were linked with data from the 1970 census from the National Bureau of Statistics in Denmark, which has data on occupational status for 1,768,846 men between 15 and 74 years of age. From this census, we ascertained a group of 124,766 "solvent-exposed" men and an "unexposed" group of 87,501 male electricians, bricklayers, and butchers. Over a follow-up period of 20 years, we observed no increase in the incidence of multiple sclerosis among men presumed to be exposed to organic solvents. It was not possible to obtain data on potential confounders, and the study design has some potential for selection bias. Nevertheless, the study does not support existing hypotheses regarding an association between occupational exposure to organic solvents and multiple sclerosis. 相似文献
5.
L Guasti P Grimoldi A Diolisi MR Petrozzino G Gaudio AM Grandi MG Rossi A Venco 《Canadian Metallurgical Quarterly》1998,31(5):1146-1150
The cardiovascular system shares numerous anatomic and functional pathways with the antinociceptive network. The aim of this study was to investigate whether angiotensin-converting enzyme (ACE) inhibitor treatment could affect hypertension-related hypalgesia. Twenty-five untreated hypertensive patients, together with a control group of 14 normotensive subjects, underwent dental pain perception evaluation by means of a pulpar test (graded increase of test current applied to healthy teeth). After the evaluation of the dental pain threshold (occurrence of pulp sensation) and tolerance (time when the subjects asked for the test to be stopped), all the subjects underwent a 24-hour ambulatory blood pressure monitoring. The hypertensive group then was treated with 20 mg/d enalapril, whereas the normotensive subjects remained without any treatment. After a time interval of 6+/-2 months, the dental pain sensitivity was retested in all the subjects, and ambulatory blood pressure was recorded during treatment in the hypertensive patients. At the first assessment, hypertensive patients showed a higher pain threshold than normotensive subjects (P<.001). On retesting of pain sensitivity in hypertensive patients, a significant decrease of both pain threshold and tolerance, leading to their normalization, was observed during treatment (P<.001 and P<.005, respectively), in the presence of reduced 24-hour and office blood pressure values. A slight, though significant, correlation was observed between variations in pain tolerance and baseline blood pressure changes occurring during treatment. During follow-up, the normotensive subjects did not show any significant pain perception or office blood pressure changes. Hypertension-related hypalgesia was confirmed. Mechanisms acting both through lowering of blood pressure and specific pharmacodynamic properties may account for the normalization of pain sensitivity observed in hypertensive patients during treatment with ACE inhibitors. 相似文献
6.
M Clodi R Oberbauer W Waldh?usl G Maurer GM Kostner K Kostner 《Canadian Metallurgical Quarterly》1997,40(12):1455-1460
Lp(a), one of the most atherogenic lipoproteins, is believed to contribute significantly to vascular diseases in non-insulin-dependent diabetic (NIDDM) patients. Contradictive data have been published on these patients concerning plasma concentrations of Lp(a) and their relation to renal function. Since apo(a) fragments appear in urine, we measured urinary apo(a) in 134 NIDDM patients and 100 matched controls and related urinary apo(a) concentrations to plasma Lp(a) levels and kidney function. Plasma Lp(a) values were found to be significantly higher in NIDDM patients. NIDDM patients also secreted significantly more apo(a) into their urine as compared to control subjects. There was no correlation between creatinine clearance or albumin excretion and urinary apo(a) concentrations. Patients with macroalbuminuria exhibited a twofold higher apparent fractional excretion of apo(a) in comparison to patients with normal renal function. Urinary apo(a) values in both patients and control subjects were highly correlated to plasma Lp(a), yet no correlation was found with HbA1c or serum lipoproteins. It is concluded that urinary apo(a) excretion is correlated to plasma Lp(a) levels but not to creatinine clearance in patients suffering from NIDDM. 相似文献
7.
M Tamura H Sasano T Suzuki T Fukaya Y Funayama K Takayama R Takaya A Yajima 《Canadian Metallurgical Quarterly》1995,10(7):1891-1896
Immunolocalization of transforming growth factor-alpha (TGF alpha), epidermal growth factor (EGF), cripto-1, amphiregulin and epidermal growth factor receptor (EGFR) was studied in 51 premenopausal human ovaries at various phases of the menstrual cycle. Localization of mRNA for TGF alpha and EGF was also studied by in-situ hybridization. Immunoreactive TGF alpha was observed predominantly in theca cells in 12 of 33 antral follicles in the follicular phase (6/14 dominant follicles, and 6/19 non-dominant) but not in any of the 18 follicles in the luteal phase or in primordial and pre-antral follicles. TGF alpha immunoreactivity was present predominantly in the luteinized granulosa cells in 13 of 15 corpora lutea in the luteal phase, which are considered to be active in steroidogenesis, but not in any of the regressed corpora lutea. Accumulation of TGF alpha mRNA hybridization signal was observed only in the theca cells in the follicles and luteinized theca cells in the ovaries that were immunohistochemically positive for TGF alpha. EGFR immunoreactivity was detected in 24 of 33 antral follicles in the follicular phase and in two of 18 follicles in the luteal phase but not in any of the corpora lutea. Immunoreactive EGF, cripto-1 and amphiregulin or EGF mRNA was not detected in any follicles, corpora lutea, or the stroma cells examined. These results indicate that, of the epidermal growth factors examined in this study, TGF alpha is locally synthesized in normal cycling human ovaries and TGF alpha may be synthesized in theca cells and act on the granulosa cells in a paracrine fashion through the EGFR in ovarian follicles. 相似文献
8.
Because epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), and epidermal growth factor receptor (EGFR) have been implicated in the regulation of adrenocortical function, we used immunohistochemistry and in situ hybridization of EGF and TGF-alpha to study 41 specimens of human adrenal cortex, including 10 normal specimens, 15 aldosteronomas, five Cushing's adenomas, six adrenocortical incidentalomas, and five carcinomas to determine what role these growth factors play in controlling human adrenocortical function. Neither immunoreactivity nor mRNA hybridization signals to EGF was detected in any specimens, and EGF therefore may exert its effects on adrenal function as an endocrine hormone. TGF-alpha expression was detected at both protein and mRNA levels in normal and neoplastic adrenal cortex, demonstrating that TGF-alpha is synthesized locally in human adrenal cortex. TGF-alpha expression was observed in the cells with increased steroidogenesis, including compact tumor cells and zona fasciculata cells with lipid depletion, but did not necessarily correlate with production sites of any specific steroid hormone. EGFR immunoreactivity was more widely distributed than TGF-alpha immunoreactivity. Both TGF-alpha and EGFR expression were markedly elevated in adrenocortical carcinomas. TGF-alpha and EGFR thus appear to be involved in biological function in both normal and neoplastic human adrenal cortex. In addition, TGF-alpha and EGFR may play important roles in some biological features of adrenocortical malignancy. 相似文献
9.
Increased rate of salivary epidermal growth factor secretion in patients with juvenile periodontitis
M Hormia I Thesleff J Perheentupa K Pesonen L Saxén 《Canadian Metallurgical Quarterly》1993,101(3):138-144
We compared salivary epidermal growth factor (EGF) concentrations in patients with juvenile periodontitis (JP) and periodontally healthy controls. In initial screening of 45 JP patients and a group of healthy controls, significantly higher salivary EGF concentrations were measured in the JP patients. Subsequently, 17 JP patients who had high EGF concentrations in some of their salivary samples were chosen, and a group of age- and sex-matched controls was selected. We then examined their EGF concentrations and EGF secretion rates under standardized conditions in stimulated and unstimulated saliva and studied the expression of EGF receptor (EGF-R) in their gingival tissues. The results showed that the mean EGF concentration (pmol/ml) was slightly higher in JP patients than in controls. However, the difference was statistically significant only in stimulated saliva and when calculated per milligram salivary protein. When EGF release was measured as the rate of EGF secretion (pg/min), significantly higher values were observed in JP patients than in controls both in unstimulated and stimulated saliva. Immunofluorescence microscopy (IF) of gingival samples from JP patients and their controls revealed no quantitative or qualitative differences in the expression of EGF-R. Our results demonstrate the complex nature of salivary EGF release. The elevated rate of salivary EGF secretion in JP patients may be associated with the pathogenetic mechanisms of juvenile periodontitis. 相似文献
10.
MA Helmrath CE Shin CR Erwin BW Warner 《Canadian Metallurgical Quarterly》1998,33(7):980-4; discussion 984-5
BACKGROUND/PURPOSE: Intestinal adaptation after massive small bowel resection (SBR) is augmented by epidermal growth factor (EGF) via an unknown mechanism. We recently have observed that EGF increases the expression of EGF receptor mRNA and protein content in the remnant ileum after SBR. The purpose of this study was to determine whether the magnitude of EGF-induced receptor expression correlates with intestinal adaptation. METHODS: A 50% proximal SBR or sham operation (bowel transection with reanastomosis) was performed on male ICR mice. Animals from each group were then selected randomly to receive either human recombinant EGF (150 microg/kg/d) or saline by twice daily intraperitoneal injections. The remnant ileum was harvested at 1 week, and parameters of adaptation measured as changes in protein content. Ileal EGF receptor mRNA was quantitated using a ribonuclease protection assay. Changes in the expression ileal EGF receptor protein were determined by Western blot after immunoprecipitation. Comparisons of mean values between groups was performed using analysis of variance (ANOVA) and a P value of less than .05 was considered significant. Values are presented as mean +/- SEM. RESULTS: EGF was mitogenic to the ileum after sham operation as monitored by increases in ileal protein content (2.21 +/- 0.002 mg/cm Sham v 2.97 +/- 0.25 mg/cm Sham +/- EGF; P < .05). After SBR, adaptation resulted in increased ileal protein content (4.45 +/- 0.27 mg/cm), which was substantially boosted by EGF (5.98 +/- 0.39 mg/cm; P < .05). No differences were detected in ileal EGF receptor mRNA or protein expression between Sham or SBR groups that did not receive EGF. However, EGF significantly enhanced the expression of ileal EGF receptor mRNA to an equal extent after both sham and SBR (approximately threefold). The magnitude of this increase in EGF receptor protein (four- to sixfold) was similar in both EGF groups as shown by Western blotting. CONCLUSIONS: Changes in ileal EGF receptor expression are not mandatory for adaptation to occur. EGF upregulates the expression of mRNA and protein for its own intestinal receptor in vivo. Because EGF-induced receptor expression was comparable after both SBR and Sham operation, the beneficial effect of EGF during adaptation is likely caused by other factors in addition to increased receptor expression. 相似文献
11.
Changes in expression of epidermal growth factor (EGF) receptors by gonadotropes parallel those of GnRH receptors. Gonadotropes increase their expression of EGF receptors (EGFR) during diestrus to reach a peak on the morning of proestrus. This is followed by a decline in expression to reach a nadir by estrus. We hypothesized that regulatory factors that stimulate changes in GnRH receptors might mediate the same changes in EGFR. To test this hypothesis, pituitary cells were collected from cycling rats and grown overnight in media with or without serum, 100 pM estradiol, or 60 ng/ml activin. On the next day, some of the cultures were further stimulated with 1 nM GnRH (4 h). The cells were then dual-labeled for EGFR and LHbeta or FSHbeta antigens and analyzed for their content of EGFR and gonadotropins. Neither activin nor estradiol increased percentages of cells with gonadotropin antigens and EGFR. Estradiol decreased percentages of cells with EGFR and LH in proestrous rats and those with EGFR and FSH in diestrous rats. The estradiol-mediated decline in EGFR expression during proestrus is similar to that seen when GnRH receptors are studied. Serum containing media alone increased percentages of LH and FSH cells with EGFR in populations from estrous or metestrous rats. Therefore, further experiments were conducted to learn if serum factors or EGF might be a regulator. Removal of serum from the growth media did not prevent the increase in percentages of LH cells with EGFR over the 18-h growth period. However, removal of serum did prevent the increased percentages of FSH cells with EGFR. Similarly, adding 1:100 anti-EGF to the serum containing media did not affect expression of EGFR by LH cells. However, it did cause a 27% decrease in percentages of FSH cells with EGFR. Finally, when 10 ng/ml EGF was added to metestrous populations in serum-free media there was a 1.4-1.5-fold increase in percentages of LH or FSH cells with EGFR. Collectively, these studies show that EGF receptors are not stimulated in gonadotropes by the same hormones that up-regulate GnRH receptors. Furthermore, EGF itself may be among the factors that up regulate EGFR in gonadotropes. EGF receptors may be down-regulated by estradiol during proestrus, but the effect is limited to LH cells. Finally, EGF's differential effects on LH and FSH cells suggests that it may selectively act on monohormonal gonadotropes. EGF receptors may be a marker for a unique subset of developing gonadotropes. 相似文献
12.
JR Cook HA Glick W Gerth B Kinosian JB Kostis 《Canadian Metallurgical Quarterly》1998,11(12):1433-1441
This study examined the effect of enalapril on survival, resource use, and cost of care in patients with left ventricular dysfunction and hypertension using a retrospective analysis of patients who participated in the Studies of Left Ventricular Dysfunction (SOLVD). Among the 6797 SOLVD participants, 1917 patients had either elevated systolic (> or = 140 mm Hg) or diastolic (> or = 90 mm Hg) blood pressure. Therapy with enalapril was associated with a significant relative risk reduction for mortality (RR = 0.819, 95% CI: 0.68 to 0.98; P = .03). This resulted in a gain of 0.11 years (95% CI: 0.00 to 0.20 years) of survival during the average 2.8 year follow-up for this subgroup and was projected to result in a gain of 2.14 years (95% CI: 0.05 to 4.21 years) during the patient's lifetime. Enalapril significantly reduced the risk of first hospitalization for heart failure by 37%. For all types of hospitalizations, there was an average reduction of 32 hospitalizations per 100 patients treated with enalapril during the trial period (95% CI: 11.8 to 52.2 hospitalizations avoided per 100 patients), resulting in an estimated net savings of $1656 per patient during the trial period (95% CI: increased cost of $191 to savings of $3502). Although the projected lifetime net savings of $1456 was not significant (95% CI: increased cost of $9243 to saving of $12,527), evaluation of the cost per life year saved indicated that enalapril represented a cost-effective strategy. The estimated clinical benefit of enalapril among the hypertensive subgroup in SOLVD supports the recommendation that angiotensin converting enzyme (ACE) inhibitors should be considered as first line pharmacologic therapy for hypertensive patients with left ventricular dysfunction. From both the clinical and economic viewpoints, ACE inhibitors provide important clinical benefits and are cost-effective. 相似文献
13.
The majority of the mRNA molecules in HeLa cells contain 1-2 residue(s) of m6Ap and one blocked, methylated 5' terminal "cap" structure. The hnRNA, which is longer than mRNA, contains both m6Ap and caps but 4-6 times as many m6Ap residues per chain. In addition, nuclear molecules contain T2 RNA ase-resistant, methyl-labeled oligonucleotides ("di-" and "tri-" nucleotides) which are not found in mRNA. Some of the dinucleotides may be precursors to the 2'-0-methylated nucleotides in the cap structures. These results are compatible with internal methylation of hnRNA molecules (both m6Ap and 2'-0-methyl) followed by hnRNA cleavage and the addition of the cap structure to generate at least some of the HeLa cell mRNA. It also appears that some hnRNA molecules, which are longer than most mRNA molecules, contain cap structures suggesting the derivation of some mRNA molecules from the 5' regions of hnRNA. 相似文献
14.
The role of glutamate as a possible mediator of neurodegeneration is well described, and the homeostasis of extracellular glutamate is considered of major importance when addressing the pathogenesis of excitatory neurodegeneration. Applying the 'indicator diffusion' method to the microdialysis technique, we present a method that is suitable for the in vivo investigation of the capacity of cellular uptake of glutamate. Using 14C-mannitol as reference, we measured the cellular extraction and the cell membrane permeability of the test substance 3H-D-aspartate in the corpus striatum of the rat brain. The cellular extraction fraction of 3H-D-aspartate was 0.29, and the cell membrane permeability 2.24 x 10(-4) cm/s. In the presence of the glutamate-uptake blocker DL-threo-beta-hydroxyaspartate (THA) the extraction of 3H-D-aspartate was completely abolished, indicating that extraction of 3H-D-aspartate was due to cellular uptake by glutamate transporters. The cell membrane permeability towards 3H-D-aspartate was reduced by approximately 98% due to THA, indicating that the cell membranes per se are highly resistant to diffusion of 3H-D-aspartate. It is concluded that the present method can be used in studying the capacity of the glutamate transporters in vivo. 相似文献
15.
P Rockwell WJ O'Connor K King NI Goldstein LM Zhang CA Stein 《Canadian Metallurgical Quarterly》1997,94(12):6523-6528
Antisense oligodeoxynucleotides offer potential as therapeutic agents to inhibit gene expression. Recent evidence indicates that oligodeoxynucleotides designed to target specific nucleic acid sequences can interact nonspecifically with proteins. This report describes the interactive capabilities of phosphorothioate oligodeoxynucleotides of defined sequence and length with two essential protein tyrosine receptors, flk-1 and epidermal growth factor receptor (EGFR), and their effects on receptor signaling in a transfected and tumor cell line, respectively. Phosphorothioate oligodeoxynucleotides bound to the cell surface, as demonstrated by fluorescence-activated cell-sorter analyses (FACS), and perturbed receptor activation in the presence and absence of cognate ligands, EGF (EGFR) and vascular endothelial growth factor (flk-1), in phosphorylation assays. Certain phosphorothioate oligodeoxynucleotides interacted relatively selectively with flk-1 and partially blocked the binding of specific anti-receptor monoclonal antibodies to target sites. They stimulated EGFR phosphorylation in the absence of EGF but antagonized ligand-mediated activation of EGFR and flk-1. In vivo studies showed that a nonspecific phosphorothioate oligodeoxynucleotide suppressed the growth of glioblastoma in a mouse model of tumorigenesis. These results emphasize the capacity of phosphorothioate oligodeoxynucleotides to interact with cells in a sequence-selective nonantisense manner, while associating with cellular membrane proteins in ways that can inhibit cellular metabolic activities. 相似文献
16.
Characterization of the epidermal growth factor receptor in pig oviduct and endometrium 总被引:1,自引:0,他引:1
K Wollenhaupt U Tiemann R Einspanier F Schneider W Kanitz KP Brüssow 《Canadian Metallurgical Quarterly》1997,111(2):173-181
Two different plaque variants of Japanese encephalitis virus were selected from a wild-type Taiwanese isolate using Vero cells. One variant was found to exhibit small plaque morphology with retarded virus replication kinetics in Vero cells, and was demonstrated to be resistant to monoclonal antibody (mAb) E3.3 neutralization. The other variant showed large plaque morphology, was sensitive to mAb E3.3 neutralization, and manifested reduced virulence in mice on both intracranial and intraperitoneal inoculations. These two variants propagated in Vero cells retained high levels of infectivity but had relatively low HA titers as compared with the parent strain. The envelope sequences of these two variants showed four amino acid differences at residues E-85 (Glu/Arg), E-306 (Glu/Gly), E-331 (Ser/Arg), and E-387 (Met/Arg). Our results indicated the neutralizing epitope of Japanese encephalitis virus did not overlap with virus virulence determinant. 相似文献
17.
H Sato M Iwano Y Akai H Kurioka A Kubo T Yamaguchi E Hirata M Kanauchi K Dohi 《Canadian Metallurgical Quarterly》1998,18(6):490-494
Two cases of double outlet right ventricle with restrictive ventricular septal defect are described. This is an uncommon presentation that causes left ventricular dysfunction because of left ventricular outflow tract obstruction. The presence of an intact atrial septum leads to severe pulmonary hypertension, which tends to aggravate the right ventricular output. In the presence of a normal left ventricle, the authors suggest the possibility of enlargement of the ventricular septal defect in order to perform a biventricular repair. The association of a supramitral valve ring in both cases, and the isolation of the left subclavian artery and an aortopulmonary fenestration in one of these cases, are also discussed. In addition we explore factors that cause restrictive ventricular septal defects as well as the mechanisms that may lead to spontaneous closure of ventricular septal defect in a double outlet right ventricle. 相似文献
18.
Epidermal growth factor (EGF) is a conventional mitogenic factor that stimulates the proliferation of various types of cells including epithelial cells and fibroblasts. EGF binds to and activates the EGF receptor (EGFR), which initiates intracellular signalling and subsequent effects. The EGFR is expressed in neurons of the cerebral cortex, cerebellum, and hippocampus in addition to other regions of the central nervous system (CNS). In addition, EGF is also expressed in various regions of the CNS. Therefore, EGF acts not only on mitotic cells, but also on postmitotic neurons. In fact, many studies have indicated that EGF has neurotrophic or neuromodulatory effects on various types of neurons in the CNS. For example, EGF acts directly on cultured cerebral cortical and cerebellar neurons, enhancing neurite outgrowth and survival. On the other hand, EGF also acts on other cell types, including septal cholinergic and mesencephalic dopaminergic neurons, indirectly through glial cells. Evidence of the effects of EGF on neurons in the CNS is accumulating, but the mechanisms of action remain essentially unknown. EGF-induced signalling in mitotic cells is better understood than that in postmitotic neurons. Studies of cloned pheochromocytoma PC12 cells and cultured cerebral cortical neurons have suggested that the EGF-induced neurotrophic actions are mediated by sustained activation of the EGFR and mitogen-activated protein kinase (MAPK) in response to EGF. The sustained intracellular signalling correlates with the decreased rate of EGFR down-regulation, which might determine the response of neuronal cells to EGF. It is likely that EGF is a multi-potent growth factor that acts upon various types of cells including mitotic cells and postmitotic neurons. 相似文献
19.
IP Sokolova AM Arnautov AD Blagoveshchenskaia NN Nikol''ski? ES Kornilova 《Canadian Metallurgical Quarterly》1998,40(10):855-861
Although interferon-alpha (IFN-alpha) has proved beneficial in the treatment of some tumors, the basis for this is still uncertain. In this study, we examined the effects of IFN-alpha on the growth of tumor cells in vitro, using the Daudi line of B lymphoma cells as a model. There was a dose-dependent accumulation of these cells in the G1 phase of the cell cycle 24-48 h from the time of exposure to IFN-alpha. This was followed between 48 h and 96 h by an increasing degree of apoptosis, as assessed by cell survival, propidium iodine staining, and transmission electron microscopy. Concomitantly with the apoptosis, there was the appearance of pl8 Bax-alpha, an apparently novel variant low molecular weight form of the p21 Bax-alpha found in normal cells. There was also a slight diminution in Bcl-xL, with a resultant drop in the Bcl-xL:Bax-alpha ratio. Treatment of cells with CD40-L partially inhibited the development of apoptosis in response to IFN-alpha. At the same time, generation of p18 Bax-alpha was reduced, which suggests that this plays a part in the apoptotic process. These findings may throw light on the development of lymphomas and perhaps point to future ways of improving therapy with IFN-alpha. 相似文献
20.
K Maehiro S Watanabe M Hirose R Iwazaki H Miwa N Sato 《Canadian Metallurgical Quarterly》1997,32(5):573-578
We assessed the influence of epidermal growth factor (EGF) and insulin on gastric epithelial restoration in vitro. Rabbit gastric epithelial cells were cultured and formed a complete monolayer cell sheet in 2 days. We created a wound (1.8 +/- 0.05 mm2) by denuding an area of cells, and EGF (0.1-30 ng/ml) and/or insulin (1 nM-1 microM) was added. The restoration process, which included cell migration and proliferation, was monitored by measuring the cell-free area every 12 h for 2 days. Proliferating cells were detected by sequential staining with bromodeoxyuridine (BrdU). Control cells showed complete repair in 36-48 h and restoration was accelerated dose-dependently by EGF or insulin. EGF plus insulin further accelerated restoration, which was then completed in 12-24 h. EGF and/or insulin increased the number of BrdU- positive cells. The results indicated that EGF and insulin additively accelerated gastric epithelial wound repair by stimulating both the migration and the proliferation of gastric epithelial cells (particularly the former). 相似文献